Module 6:

6.2 Turf problems and controls

1   Pest control

A number of controls will be quite generic, suitable for more than one pest, whilst others might be specific to a particular pest.

2   Earthworms

1. Keep the turf and soil profile on the drier side - do not overwater.
2. Brush (drag brush or power brush) to disperse surface casts.
3. Adjust soil pH to be more acidic, or at least the surface layer to be made more acidic, to reduce the casting potential of earthworms. Take care not to over acidify and reduce the competitiveness of desirable grasses.
4. Box off grass clippings when earthworm activity is increasing, as this removes a potential food source for them.
5. Scarify to remove dead and decaying material and remove arising as this is also another food source.
6. Apply non-organic fertilisers and those with an acidic soil reaction.
7. Apply top-dressings that are more on the acidic side.
8. Keep the pitch well aerated during the colder months as allowing cold air into the soil profile will encourage earthworms to move away from the cold.
9. Apply a soil conditioner that also helps to reduce earthworm activity where it creates an irritation barrier to reduce earthworm progression to a pitch surface from within the soil profile.
10. Apply an approved earthworm chemical control, although there may not be any available at the time.

3   Chafer grubs & Leatherjackets

1. Keep the turf and soil profile on the drier side - do not overwater.
2. Scarify to remove any thatch build-up thereby reducing a potential protective blanket for development of the eggs and grubs.
3. Aerate regularly during colder weather to allow cold air to penetrate into the soil profile where grubs may be located.
4. Disc aerate at close spacings to potentially squash or cut into grubs within the soil profile.
5. Encourage deeper rooting and increased root density to counter (to some extent) grubs nibbling away at roots.
6. Apply an approved bio-pesticide or insecticide at the appropriate time where monitoring has indicated there may be a high number of adults laying eggs.

4   Birds and mammals

By controlling grubs and earthworm activity this should significantly reduce the subsequent activity of birds and some mammals (especially badgers) in searching for any pests within the soil profile.

Badgers might also eat grass seed, although this would probably be as part of searching for grubs and earthworms rather than specifically targetting grass seed.

Some birds, especially pigeons, can be a particular problem at renovation time when relatively large quantities of grass seed are used as part of the renovation programme. Hiring specialists who handle birds of prey, at this time of the year, would scare off birds and reduce seed loss, although the cost of hiring might far outweigh the negative impact of actual seed loss and speed of uniform sward establishment.

Some form of fencing or barriers might help reduce the likelihood of some mammals gaining access to a pitch, but again the cost might be prohibitive and unreasonable when compared to what might be called typically minor damage and the speed of repairs that can be carried out.

5   Nematodes

A few species will mainly be a potential issue on high-class specially constructed sand-based pitches that are intensively maintained, being much less likely of a problem on soil-based pitches that are maintained in less intensive ways to the premium grade pitches.

1. Keep the turf on the drier side - do not overwater nor water too frequently.
2. Encourage a deeper rooting sward through good aeration practices.
3. Maintain a healthy, strong sward by applying appropriate quantities of fertiliser.
4. Apply adequate amounts of biostimulants to counter low levels in sand-based pitches.
5. Do not mow too short as this reduces rooting depth, density and sward resilience. Do not overstress the sward with short mowing as this will make it more susceptible to nematode damage.
6. Keep the surface layer clean of dead and decaying organic matter through scarification, metal tine raking and verticutting.
7. Aim to reduce the amount of shade on a pitch.
8. Apply any approved biological or chemical controls, where nematode activity is higher than a planned threshold or damage is trending towards an unacceptable level.

Now that we have looked at some of the more typical pests that might be encountered as well as some potential ways in which they might be control and extent of damage reduced, we will take a brief look at some of the more common turfgrass diseases that might be encountered for the more abundant pitche that would typically be quality graded 1 to 3.